G74SX Keyboard backlight disabled

Discussion in 'ASUS Gaming Notebook Forum' started by Sir Robin, Apr 25, 2012.

Thread Status:
Not open for further replies.
  1. Sir Robin

    Sir Robin Notebook Geek

    Reputations:
    8
    Messages:
    84
    Likes Received:
    5
    Trophy Points:
    16
    Sometime recently, the keyboard backlight on my G74SX stopped
    working. I'm not exactly sure when it happened. I wasn't watching
    it too closely. It was working, when my system came back from the
    dead (flash reprogram), but it has quit doing so. I have searched the
    forums, and tried all of the standard fixes, including ATK package
    removal/reinstall, keyboard filter etc. So far, nothing has produced a
    change in behavior. At the Window 7 level, Fn-F3/F4 have no effect,
    and do not cause any sort of OSD message. All of the other Fn keys
    work fine. At the BIOS level, I do not see the keyboard lights flicker
    on/off, during the Asus splash screen. This leads me to believe that the
    problem is at the BIOS level. It acts like a static memory variable has
    been set the wrong way (not sure how), and nothing in the code is
    returning it to it's correct value. The only thing I've done recently, is
    remove bloatware, so it may have something to do with deleting
    Asus applications. I have not dismantled my G74SX, so I do not suspect
    that any cables have come loose. During searches, I found this
    issue, from the G73 series:

    http://forum.notebookreview.com/asus-gaming-notebook-forum/490250-asus-g73jh-keyboard-light-failure-after-bios-flash-209-a-34.html

    That problem sounds identical to the one I'm seeing. Assuming Asus did not
    completely re-invent the wheel, on the next model, it is possible that the same
    problem exists, on the G74SX.

    So, has anyone else with a G74SX run into this problem? If so, were you able
    to resolve it? Lastly, has anyone tried Gary's G73 fix on the G74SX?

    Thanks, in advance, for you help,

    Sir Robin
     
    headealer likes this.
  2. dstrakele

    dstrakele Notebook Consultant

    Reputations:
    66
    Messages:
    199
    Likes Received:
    0
    Trophy Points:
    30
    Since you report the keyboard lights WERE working after the BIOS flash, I would try entering the BIOS and "Load Optimized Defaults" (F9). As you observed, it is important the lights flash on startup. If they don't, there's nothing that can be done in Windows to bring 'em back.

    Alternatively, you could try to reflash the BIOS or check the keyboard light cable connection.

    If.that fails, call your nearest ASUS Service Center. They should be able to quickly resolve the issue if it is BIOS-related.
     
  3. Sir Robin

    Sir Robin Notebook Geek

    Reputations:
    8
    Messages:
    84
    Likes Received:
    5
    Trophy Points:
    16
    Thanks for the feedback dstrakele! :)

    Sounds like the disconnect is somewhere at the BIOS
    level. I will play around with it, and see if I can figure out
    where the problem lies. If it remains a mystery, I will follow your
    advice, and contact the service center.

    Sir Robin
     
  4. Sir Robin

    Sir Robin Notebook Geek

    Reputations:
    8
    Messages:
    84
    Likes Received:
    5
    Trophy Points:
    16
    Okay, my keyboard backlights are on again! :)

    The G74SX appears to be subject to the same problem as the
    G73 series. Somewhere, in the BIOS, there is a variable, that, if changed,
    causes the backlight support code to be skipped (lack of backlight display
    during Asus splash screen). This same code must also be responsible for the
    ACPI entry, which tells the windows driver how to handle the Fn key press
    events. I suspect this is why windows can not recover the lights, once the
    variable is corrupted. I do not yet know the exact cause of the variable
    corruption, but I suspect it has something to do with uninstalling Asus
    apps, which talk to the ATK driver module. BTW, Asus, if you are reading
    this, please update the BIOS to check/initialize the variable, every time the
    system is booted.

    Here is how I fixed the problem:

    1. Asked a buddy (with working backlight) for a snapshot of his working BIOS
    code (V202, see below)
    2. Updated my BIOS, with his snapshot, using Easyflash (with a FAT32 formatted USB drive)
    Upon restart, the keyboard lights turned on and off, during Asus splash screen (yahoo!)
    3. Entered setup and restored default values
    Lights still worked
    4. Updated my BIOS to V203, from the Asus website, using Easyflash
    Lights still worked
    5. Entered setup and restored default values
    Lights still worked
    6. Booted into Windows. Lights were off. Pressed Fn + F4, lights came on, OSD
    registered the key presses
    7. Shutdown and rebooted, all worked as expected, backlight brightness was remembered
    8. Made a snapshot of my working BIOS, for future "backlight fixing", if needed :)

    Regarding step #1, it appears that Asus does not update the entire SPI flash,
    when you do a BIOS update. It only updates the last 2.5MB of the flash.
    This section contains the BIOS code, non-volatile variable storage, bios extensions,
    and EC code, etc). This is the stuff that is common among all of the units. The
    BIOS update files, available on Asus's website, are snapshots of this 2.5MB area,
    with the various data sections initialized to their default values. Using available
    tools, you can make a similar snapshot of your working BIOS. This snapshot will include
    any Setup changes you've made (current state of any non-volatile variables). It
    appears that one of these non-volatile variables stores the keyboard backlight
    presence and/or brightness value. If you make a snapshot of a working BIOS, from
    a unit, with an operational keyboard backlight, you also get a copy of that correct
    variable setting. Unfortunately, the Asus update files do not appear to have
    this variable set correctly (not sure how this can be). I originally tried all three
    Asus bios images (V201 - V203, using Easyflash). None of them would bring my
    backlight back to proper operation. Restoring defaults also did not fix the issue.
    Only a working BIOS, from a working backlight unit, would re-enable the backlight.

    So here is my recommendation, for anyone who is concerned about this issue,
    and is comfortable with BIOS utilities. If your backlight is currently working,
    make a snapshot of your working bios. If it ever becomes disabled, you can
    use Easyflash, to re-enable it, with your backup copy of the working BIOS.

    Here is the thread, which outlines the tools etc:

    http://forum.notebookreview.com/asus-gaming-notebook-forum/656498-g74sx-circuit-reprogram-bios-spi-2.html

    Sir Robin
     
  5. Burberry

    Burberry Newbie

    Reputations:
    0
    Messages:
    1
    Likes Received:
    0
    Trophy Points:
    5
    Hi Sir Robin. can you upload a file of your bios? i do not have a friend with the same laptop as me. (G74sx). I really would like to have my backlights working again!! thanks :)
     
  6. Sir Robin

    Sir Robin Notebook Geek

    Reputations:
    8
    Messages:
    84
    Likes Received:
    5
    Trophy Points:
    16
    Hi Burberry,

    Sure, I can PM you a copy, but first, perhaps you could
    do me a favor? :) I need some examples of the problem, so
    I can track down which variable location is the likely culprit.
    Once I have the location(s) nailed down, I can update Gary's
    fix, for the G74SX. Would you be willing to send me a snapshot
    of your working bios (with the backlights disabled)? It would
    also be helpful to know which bios version you are running, and
    your full model number. I recommend using PM, to send the image/link.
    It is not clear how much system unique info is stored in the working
    bios. To make the snapshot, just follow the above link, and use
    AFUWIN Aptio version. If you need help running the tool, I can
    post instructions.

    Do you know what caused the BL's to stop working? Were you
    recently removing the bloatware? I'm still trying to figure out what
    causes the lights to become disabled. To confirm you are experiencing
    the same problem, can you verify that the blacklights do not flash
    during the initial Asus splash screen (early bios boot)?

    Thanks,

    Sir Robin
     
  7. Evan_M

    Evan_M Newbie

    Reputations:
    0
    Messages:
    4
    Likes Received:
    0
    Trophy Points:
    5
    Hi, Sir Robin.

    I got exactly the same problem. I have bricked my laptop when updating bios from 202 to 203. Guys from Asus service center fixed it, but now the backlight is completely off (nothing on startup and on fn+f4). Current bios version is 203. So the problem appeared exactly after bios fixture was made in service center :) I would greatly appreciate if you send me the snapshot with working backlight.
    My laptop model is G74SX-DH71. I’m also ready to send you my BIOS snapshot made with APTIO.
     
  8. Sir Robin

    Sir Robin Notebook Geek

    Reputations:
    8
    Messages:
    84
    Likes Received:
    5
    Trophy Points:
    16
    Hi Evan_M,

    Could you please enable private messaging, on your account?
    I am not able to send you anything :(

    Sir Robin
     
  9. Evan_M

    Evan_M Newbie

    Reputations:
    0
    Messages:
    4
    Likes Received:
    0
    Trophy Points:
    5
    Sorry, I'm afraid I can't. This FAQ page Laptop Forums and Notebook Computer Discussion - FAQ says that the registered members have private messaging section in their user CP. But I don't have any, only "Settings", Subscripted threads" and "Misc". "Settings" also doesn't contain anything regarding messaging.
    Can you please send your snapshot to my email (inm6561@gmail.com) or to Free large file hosting. Send big files the easy way! ? I would also ask you to describe the correct bios flashing procedure for G74SX as far as I killed mine by using Asus flasher that is available on startup.
     
  10. Sir Robin

    Sir Robin Notebook Geek

    Reputations:
    8
    Messages:
    84
    Likes Received:
    5
    Trophy Points:
    16
    Sure, I'll try contacting you, via that address.

    You should have the ability to enable PM's. Look at top
    right corner of your forum window. There should be a
    welcome message, along with a summary of your private
    messages. If you click that link, it will take you to the
    account control page. You can then select "edit options",
    to change your PM controls.

    Good luck,

    Sir Robin
     
Loading...
Thread Status:
Not open for further replies.

Share This Page